Misc Flashcards
Menetrier Disease. Gastric related
Hyperplasia of gastric (stomach) mucosa. Mainly glandular secretion of mucous and super-hypertrophied stomach rugae (look like brain gyri). Parietal cells die, subsequent achlorhydria.
Precancerous
Mallory bodies found on liver biopsy. What are they, and what are their significance?
Eosinophilic inclusions of damaged keratin filaments
Found in alcoholic hepatitis
Aspergillus causes what hepatic abnormality. Mediated by what toxin?
Aflatoxin from aspergillus –> hepatocellular carcinoma
Two places in GI histology with PAS positive intracellar stuff?
Whipple Disease: foamy macrophages with PAS+ inclusions
Alpha-1 antitrypsin deficiency: PAS+ globules in liver
Long-term use of proton-pump inhibitors can cause what metabolic abnormality?
Hypomagnesemia! Ain’t that some shit
Also increased risk for C. diff infection
Orlistat MOA. (Hint: GI related)
Inhibits pancreatic and gastric lipase enzymes resulting in decreased fat absorption. Used in weight-loss treatments. Causes steatorrhea and decreased absorption of fat soluble vitamins
Patient presents with swollen, red, and tender calf. He says he has had a couple of these throughout his body in the last few months. They usually self resolve w/o issue. Also found to have cholestatic LFTs with elevated amylase and lipase. Dx?
Migratory Thrombophlebitis that is strongly associated with pancreatic cancer (hence the cholestatic LFTs with elevated lipase + amylase.
Diseases associated with the infamous HLA-B27 subtype
PAIR: psoriasis, anklyosing spondyolitis, IBD (UC/Crohns), Reiter syndrome (reactive arthritis)
Patient with ADPKD presents with thunderclap headache. After successful treatment, 7 days later develops focal neurologic signs. What happened? What Rx should have been used to prevent this
Subarachnoid hemorrhage from ruptured berry aneurysm (associated with ADPKD). Sequelae of cerebral vasospasm occurring a few days later. Prevent with calcium channel blocker Nimodipine specificaly
Cromolyn sodium use? (Hint: blood cells)
Prevents degranulation of mast cells. Used in asthma prophylaxis (apparently…)
Hemophilia C deficiency and inheritance?
Autosomal recessive deficiency in factor XI.
Contrast with A & B, both X linked
Difference in genetic defect in beta vs alpha thalassemia.
Alpha thalassemia has gene mutations in the gene itself. Beta thalassemia mutations are in promoter and splice site sequences
Basophillic stipiling. What is it? Associated diseases
Aggregates of rRNA that can’t be degraded because of usually lead poisoning (or sideroblastic anemia)
Distinguishing folate deficiency from B12 deficiency using labs
Folate: elevated homocysteine, normal methylmalonic acid
B12: elevated homocysteine & methylmalonic acid
Eculizumab clinical indication
Paroxysmal nocturnal hematuria
Acts to inhibit terminal activation of complement
Ristocetin (old antibiotic, no longer used for Rx humans). Usefulness as a lab test?
Ristocetin causes binding between GpIb and vWF resulting in agglutination
+Ristocetin test in Glanzmann thrombasthenia (defective GpIIb/IIIa)
-Ristocetin test in Bernard-Soulier syndrome (Defective GpIb)
TdT+ marker (flow cytometry). Significance?
Marker of early T and B cells. Think of Acute lymphocytic leukemia (in children)
t(8;14)
c-myc(8) and Ig heavy chain(14)
Burkitt’s lymphoma
t(9;22)
BCR(22) and Abl(9)
Chronic myelogenous leukemia (Rx: Imatinib)
t(11;14)
Cyclin D1(11) and Ig heavy chain(14) Mantle cell lymphoma
t(14;18)
BCL-2(18) and Ig heavy chain(14)
Follicular lymphoma
t(15;17)
M3 subtype of AML that responds to all-trans retinoic acid
Most common type of non-Hodgkin lymphoma in adults?
Diffuse large B-cell lymphoma
JAK2 mutation associated with what blood abnormality
Myeloproliferative disorders: polycythemia vera, essential thrombocytosis, myelofibrosis
Aminocaproic acid. Antidote for what?
Thrombolytics. Aminocaproic acid acts to inhibit fibrinolysis
Abciximab, eptifibatide, tirofiban. Drugs used for what? (Hint: heme/onc)
Inhibitors of GpIIb/IIIa receptor, thus decrease platelet aggregation
Etoposide, teniposide | irinotecan, topotecan MOA? (Hint: Heme/Onc)
Etoposide, teniposide: Inhibit topoisomerase II preventing appropriate DNA replication. Used as an anti-neoplastic drug.
Irinotecan, topotecan: inhibit topoisomerase I
Rituximab MOA
Monoclonal Ab against CD20. Used against B-cell neoplasms (think CLL, B-type)
Bevacizumab MOA
Monoclonal antibody against VEGF, inhibits angiogenesis. AKA - Avastin
Both Alports and Marfans have vision issues. What’s the difference?
Alports (collagen type IV defect) gets cataracts because the collagen within the lens itself is type IV.
Marfans (fibrilin1 defect) gets lens ectopy/displacement because fibrilin is an important component of the zonules that hold the lens in place.
Cilostazol & dipyridamole MOA and indications? (Hint: Heme/onc)
Both are PDE inhibitors used in treatment of peripheral arterial disease. Increased cAMP inhibits platelet aggregation and increased cGMP causes vasodilation
Anti-inflammatory cytokines
IL-10 (attenuate immune system) and TGF-beta
Costimulatory signal for T-cell and B-cell activation?
T-cell: CD28 on T-cell activated by B7 on APC
B-cell: CD40 on B-cell activated by CD40L on T-cell
Embryologic origin of anterior vs posterior pituitary
Anterior (adenohypophysis) derived from oral ectoderm (rathke’s pouch)
Posterior (neurohypophysis) derived from neuroectoderm
Significance of Ras/MAP kinase pathway (Hint: endocrine)
Activated by insulin tyrosine kinase receptors. Stimulates cell growth & DNA synthesis
GLUT-2 significance
Insulin independent, bidirectional movement of glucose. Found in beta-islet cells, liver, kidney, & small intestine
MSH (melanotropin stimulating hormone). Origin, significance
Secreted from intermediate lobe of pituitary, but also stimulated by CRH (just like ACTH)
Grehlin hormone. Origin, effect
Released by stomach. Stimulates hunger. Elevated in Prader-Willi syndrome
Difference b/w cortisol and thyroid hormone effects on cells?
Cortisol: upregulation of alpha1 receptors on arterioles
Thyroid: upregulation of beta1 receptors on heart
Difference b/w methimazole and Propylthiouracil
Methimazole inhibits peroxidase
PTU inhibits peroxidase & 5-deiodinase
Striae seen in cushings syndrome caused by what
Cortisol suppresses fibroblast activity in the skin, resulting in characteristic striae
Metyrapone test (hint: endocrine)
Test for adrenal insufficiency. Metyraprone inhibits final step of cortisol synthesis (11-deoxycortisol–>cortisol). If ACTH remains low, this suggests adrenal insufficiency
Homer-wright rosettes characteristic of what (Hint: endocrine)
Histology finding characteristic of pediatric neuroblastoma (located in adrenal medulla or anywhere on sympathetic chain)
Bombesin & neuron-specific enolase +. N-myc oncogene overexpression
Patient with facial/periorbital edema, hypercholesterolemia, and an abnormal TSH. Dx?
Hypothyroidism. Low TSH. Thyroid hormone stimulates LDL receptor expression. When T3/T4 is low, LDLr decreases, hypercholesterolemia occurs. Remeber the edema too
Rx for thyroid storm
Propanolol, propylthiouracil, prednisolone
Most common kind of thyroid cancer
Papillary (Psammoma bodies)
Diabetic patient started on a new drug complains that he started feeling really sick after drinking just a little alcohol. What’s going on?
Disulfram-like effects seen in 1st generation sulfonylureas (chlorpropamide, tolbutamide).
Disulfram inhibits acetylaldehyde dehydrogenase
Diabetic patient recently started on a new drug. He has fractured two bones since. Previously perfectly healthy individual. What’s going on?
Glitazones (e.g. pioglitazone) increase risk of fractures. Also increase hepatotoxicity
Demeclocycline MOA
ADH antagonist. Used in Rx of SIADH
Cinacalcet MOA
Sensitizes CaSR (Calcium sensing receptor) in parathyroid gland: decreases PTH secretion
Treatment for leprosy
Lepromatous form: DRC (Dapsone, rifampin, clofazimine)
Tuberculoid form: Dapsone and rifampin
Liver biopsy of patient reveals intracellular globules that stain a purple-pinkish color on PAS stain. DIagnosis?
Alpha-1 antitrypsin deficiency. PAS stains accumulated A1antitrypsin molecules (misfolded proteins due to mutation)
Flutamide & cyproterone. Prescribed to a patient with prostate cancer
Both compete with testosterone and DHT for testosterone receptors.
Most common pathogens in aspiration pneumonia
Fusobacterium, peptostreptococcus, bacteroides
Neostigmine, MOA
Acetylcholine esterase inhibitor. Used to reverse neuromuscular blockade post-operatively. No CNS penetration (neither does pyridostigmine)
Patient has been eating seafood, then complains of “cold feels hot, and hot feels cold.” Dx?
Ciguatoxin poisoning from reef fish (e.g. barracuda, snapper, moray eel). Tonic opening of Na channels (similar clinical picture to cholinergic poisoning)
Isoproterenol MOA
Beta1 and beta2 agonist
Norepinephrine MOA and effect on HR
NE: alpha1, alpha2, (some beta1)
Causes reflex bradycardia from dramatic increase in MAP. Beta1 effects are not really felt
Good choice of antidepressant in anorexic patient?
Mirtazapine (centrally acting alpha2 antagonist). Increases appetite!
Selectivity of class II antiarrhythmics
Non-selective alpha & beta antagonists: Carvedilol, labetalol
Beta1 antag selective:(A-M) acebutolol, atenolol, betaxolol, esmolol, metoprolol
Beta1, Beta2 antag: (N-Z) nadolol, pindolol, propranolol, timolol
Clinical diagnosis of narcolepsy (lab test)?
Decreased CSF levels of hypocretin-1: normally secreted by the lateral hypothalamus, involved in maintaining wakefulness
Kidney stones that are not radio-opaque?
Uric acid stones. All others are radiopaque (hence the utility of KUB). Calcium oxalate or phosphate, Struvite (Mg ammonium sulfate, triple phosphate), and cystine are all radiopaque
Strange (but important) side effect of hydrochlorothiazide?
Can cause hyperglycemia. Would really suck in a diabetic patient. MOA unknown
Drugs known to cause seizures (or decrease seizure threshold)
Bupropion, Isoniazid, Imipenem/cilastatin, Enflurane